Willesden Green terminators

[londonstuff]

I was just on a northbound Jub, I didn't get the train number, but it was terminating at Willesden Green. Unusual but not unheard of and staff seemingly helped to tip out. However, expecting it to go in the sidings, it carried straight on, towards Dollis Hill.

What's the logic of this and is it a usual occurrence? (Oh and what does DOH lit up on a piece of trackside equipment, at about the place a conventional siding would be, mean?)

[rincew1nd]

A guess, DOH = Dollis Hill?

[marri260]

Regular scheduled Willesden Green reversers throughout the day in the timetable. West Hampstead siding will see much more regular timetabled use when the service gradually pushes untowards 36TPH in years to come, hence the plan to renew the points there in January.

During the return traffic period of Wembley events, all Wembley reversers detrain at Willesden Green, and run empty to the reverse in the siding at Wembley. Not only does this provide an empty train on the SB, which is obviously desirable (although trains from Stanmore aren't exactly busy!), but it also has the added benefit of not having to detrain in Wembley Platform 3, which I can imagine would be challenging with a large amount of customers on the platform expecting to just board the next train. The effect of extended dwell times for detrainments will obviously delay the services stuck behind too.

Assume you meant to say conventional 'signal' and not 'siding'! Each station has an official 3 letter abbreviation code so to speak, which is part of the TBTC upgrade. Locations where diverging routes are available have the equipment that will show which route is set and locked for the train. This is in addition to the target point that the T/Op will receive on the Train Operator's Display in the cab. Exactly the same thing can be found at Wembley both NB and SB etc.

So sort of like a signal clearing I suppose, yes. DOH is Dollis Hill, obviously showing that the route towards Dollis Hill had been set. Believe it is 'SDG' for the route to the siding.

[Deleted]

What I believe you're talking about there (the DOH lit up on a piece of trackside equipment) is a direction indicator.

Quoting from Rail Engineer:

In addition to these six main components, there are also rail gap indicators consisting of 3 red lights that indicate a 'dead' section of track ahead; train ready to start indicators consisting of 3 white lights operated by platform staff at terminating stations; route secure indicators at points for use in degraded mode to show the path the train must follow; direction indicators giving a text display used for when traversing non passenger moves into and out of depots.

DOH is obviously Dollis Hill, as opposed to SDG for siding.

I found this in an ASLEF submission which may shed some light.

17. Members have also expressed concerns over the change of destination tone. This is quite quiet and can be missed. With the lack of Direction Indicators at all junctions, this could lead to drivers not realising that they have been re-routed onto another branch, until such time as they end up in a platform that they were not expecting to be in. This is not helped by the relatively small script on the TOD. This is a major safety issue.

I couldn't find a picture of Willesden Green's, but here's a picture showing a direction indicator at Wembley Park northbound, illuminated to show the route is set towards Kingsbury (KIN).

www.flickr.com/photos/kevin_r_boyd/6783487492/

Zoom in, it's the screen on the left above the Entry Point (EP) sign and behind RM Hold board WEP 075, but is this the kind of thing you had in mind?

The screen on the right, by the way, is the route secure visual.

[punkman]

@marri1260 has got it spot on regarding the reason, more especially the bit about the difficulty of detraining at Wembley Park; indeed there was an American football match at Wembley yesterday.

I have to disagree though about the DOH indication PROVING the route is already set; my belief it is just an indication to the driver, who would get a proving indcation when his or her TOD gave them the OK to poceed. The reason for my thoughts thus are I'm sure I've seen a train in the middle platform (14) at Stratford with WEH (West Ham) showing on the indicator, but knowing the train wouldn't be going anywhere immediately as another was crossing its path into platform 15. As soon as that train had fully berthed I could hear points moving and the driver shut the doors and left. (A separate "Route Secure" indication would be needed if travelling in degarded conditions i.e. Restricted Manual.)

I also believe that these indicators have not been included on the Northern line, possibly leading to the part of the ASLEF report mentioned by tut (which admittedly I didn't fully read).

[Deleted]

The Direction Indicators were proposed for the Jubilee line as a double check that the train was going the correct way at diverging junctions. Aside from a couple of issues during early testing on the Jubilee there haven't been any routing problems where the TOD and DI disagree so in hindsight they were rather unnecessary and were descoped from Northern line (despite TU concerns about trains going the wrong way at Camden and Kennington) and won't be installed on SSR either. In some instances when designing a signalling implementation there is a tendency to err on the side of caution and replicate existing functions; the benefit of using the same system more than once is these can be reviewed second time around.

[Deleted]

Oct 3, 2016 15:27:19 GMT punkman said:

@marri1260 has got it spot on regarding the reason, more especially the bit about the difficulty of detraining at Wembley Park; indeed there was an American football match at Wembley yesterday.

I have to disagree though about the DOH indication PROVING the route is already set; my belief it is just an indication to the driver, who would get a proving indcation when his or her TOD gave them the OK to poceed. The reason for my thoughts thus are I'm sure I've seen a train in the middle platform (14) at Stratford with WEH (West Ham) showing on the indicator, but knowing the train wouldn't be going anywhere immediately as another was crossing its path into platform 15. As soon as that train had fully berthed I could hear points moving and the driver shut the doors and left. (A separate "Route Secure" indication would be needed if travelling in degarded conditions i.e. Restricted Manual.)

I also believe that these indicators have not been included on the Northern line, possibly leading to the part of the ASLEF report mentioned by tut (which admittedly I didn't fully read).

I agree it's implausible that the DOH indication would prove the route is locked, it merely confirms which route the train will take and would be intended for use when everything is working. Potentially very handy if you're in Stratford platform 14 with a train full of passengers, expecting to go to Stanmore and then the indicator lights up to tell you you're going down the depot. Judging by the ASLEF statement, you would get a change of destination on your TOD accompanied by an audible chime, but it seems that in ASLEF's view this is easy to miss, owing to a potentially flawed design. Obviously you should have had a radio call too, but it seems it would be very doable to close up, hit the old start buttons and suddenly find yourself and your train load of passengers on the arrivals road for Stratford Market Depot. Good to have the indicator as a line of defence against that, but clearly it's not about confirming route locking, that's all on the TOD and it's what the Route Secure Indicators are for in degraded conditions, as you rightly say.

There's an indicator on the Northern at East Finchley, platform 3. It has SDG for roads 2 - 9 of Highgate Dept and ENG for number 1 road. It must be illuminated before the train is moved, but does not itself give authority for the train to move.

[Deleted]

Oct 3, 2016 15:38:47 GMT tut said:

Judging by the ASLEF statement, you would get a change of destination on your TOD accompanied by an audible chime, but it seems that in ASLEF's view this is easy to miss, owing to a potentially flawed design.

Not sure how a TU concern about something that hasn't happened turns into a potentially flawed design. A lot of human factors design went into the TOD and audible warnings involving the TU reps. If they were concerned (which I don't think they really were) the audible alert could easily have been made louder or longer.

Even when trains are being reformed at Stratford and some put away to depot the train ops are very sharp at noticing a destination change and asking for confirmation in my experience.

The ASLEF doc seems to date to 2012-13 and is clearly intended to make a political point.

[Deleted]

Oct 3, 2016 15:48:03 GMT @tridentalx said:

Oct 3, 2016 15:38:47 GMT tut said:

Judging by the ASLEF statement, you would get a change of destination on your TOD accompanied by an audible chime, but it seems that in ASLEF's view this is easy to miss, owing to a potentially flawed design.

Not sure how a TU concern about something that hasn't happened turns into a potentially flawed design. A lot of human factors design went into the TOD and audible warnings involving the TU reps. If they were concerned (which I don't think they really were) the audible alert could easily have been made louder or longer.

Even when trains are being reformed at Stratford and some put away to depot the train ops are very sharp at noticing a destination change and asking for confirmation in my experience.

The ASLEF doc seems to date to 2012-13 and is clearly intended to make a political point.

Sorry, I could have been less sloppy, I have no idea how usable the TOD is, I was interpreting ASLEF's statement

17. Members have also expressed concerns over the change of destination tone. This is quite quiet and can be missed. With the lack of Direction Indicators at all junctions, this could lead to drivers not realising that they have been re-routed onto another branch, until such time as they end up in a platform that they were not expecting to be in. This is not helped by the relatively small script on the TOD. This is a major safety issue.

Where they seem to feel the "relatively small script on the TOD" and the "quite quiet" change of destination tone which "can be missed", "could lead to drivers not realising that they have been re-routed onto another branch". ASLEF seem to feel that this possibility arises from flaws (script on the TOD too small, audible chimes too quiet) in the design, which can be mitigated against by having a bright LED sign light up with extra information, minimising the risk of drivers "ending up in a platform that they were not expecting to be in" - or perhaps more relevantly, a depot or a siding when they still have passengers on, as ending up at Mornington Crescent, rather than Euston City is not "a major safety issue" unless passenger tempers are a lot worse than I realise.

That certainly seems to be their line of reasoning when they highlight the lack of Direction Indicators at all junctions as a factor, which I used to suggest a possible useful function of the Direction Indicators, but I was very careless in possibly suggesting that the design of the system was flawed or that I thought so. I have really no idea!

[Chris M]

2012-13 is quite a while ago now - is it possible that comments from the TU such as this one have been taken into account and the volume and/or length of the tone has been changed since the document was written?

[Deleted]

Oct 3, 2016 15:56:58 GMT tut said:

Sorry, I could have been less sloppy, I have no idea how usable the TOD is, I was interpreting ASLEF's statement

No need to apologise!

Oct 3, 2016 20:35:50 GMT Chris M said:

2012-13 is quite a while ago now - is it possible that comments from the TU such as this one have been taken into account and the volume and/or length of the tone has been changed since the document was written?

There hasn't been any change but I don't recall their safety concerns being raised during or after the design process or during commissioning (and the letter would have come to me). The only issue was around being misinformed about branch working.

Well that innocent little question about a DOH display certainly generated some discussion